<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
		<input id="username" type="" name=""  value="张三" />
	</body>
	<script type="text/javascript">
		var input =document.getElementById("username");
		console.log(input.value)
//		console.log(typeof(input))
	</script>
</html>
